A grand celebration is taking place this weekend in Philadelphia to mark the 50th anniversary of the LGBT rights movement. Hundreds of activists and notables will gather in the Gayborhood and other areas around town to participate in exhibits, panels, film screenings, concerts and parties, capped off by a 50th anniversary ceremony at Independence Hall on Saturday hosted by comedienne Wanda Sykes.

The festivities began Thursday with James Obergefell, the lead plaintiff in the recently decided Supreme Court ruling affirming same-sex marriage. He lay a wreath at the Gay Pioneers historic marker across the street from the Liberty Bell, to honor those whose activism laid the groundwork for the movement.

Most people associate the beginning of the LGBT rights movement with the Stonewall Riots in 1969, when a police raid at the Stonewall Inn caused many patrons to fight back. But four years earlier, on July 4, 1965, a group of 40 activists, led by organizers Frank Kameny and Barbara Gittings, held what was at the time the largest demonstration in support of gay rights in the world. This began what became known as the “Annual Reminders” demonstrations, strategically held each year at Independence Hall where the Liberty Bell then resided, reminding people of the Declaration of Independence’s proclamation of the right to “life, liberty and the pursuit of happiness.” After the Stonewall riots, Kameny and Gittings suspended the annual reminders to focus on organizing a demonstration to commemorate Stonewall, launching in 1970 what has since become known as NYC’s first-ever Pride Parade.

I reached out to several prominent people attending this weekend’s festivities for their thoughts on why this weekend was important, especially in light of the Supreme Court marriage ruling, and where they think the LGBT rights movement is headed.